Vortex Tube

Compressed air at high pressure can cause injury. Never direct the air streams toward people. The air jets can be quite powerful and may project debris. Keep hands and face away from outlet ports when operating.

The hot outlet can reach temperatures exceeding 150°C, while the cold outlet can drop below -40°C. Do not touch the outlet ports directly during operation. Allow the tube to return to room temperature before handling.

Purpose

Compressed air entering a vortex tube (Ranque-Hilsch tube) spontaneously separates into hot and cold streams at opposite ends. Students observe a striking, counterintuitive result that appears to violate the Second Law but is driven by angular momentum transfer from the compressed air input.

Top: Full setup showing the vortex tube on the lecture bench with two projection thermometers displayed on an overhead projector. Bottom: Close-up of the vortex tube mounted on a base plate with thermometer probes inserted into both outlet ends on rod stands.

Figure 1:

Warning: Compressed Air Hazard

Warning: Temperature Extremes

Purpose

Safety Warnings

Warning: Compressed Air Hazard

Warning: Temperature Extremes

Purpose